Carburetor



Aug. 9, 1938. J. A. PAAscl-IE cARBuREToR Filed May '7, 1934 3 Sheets-Sheet 1 llxxm Imre/1115i?. tTem/.9 J?. Pache,

WMM WAC/3752 Aug. 9, 1938. J. A, PAAscHE CARBURETOR Filed May '7, '1934 5 Sheets-Sheet 2 v l w. w 2%/ MQ Aug. 9, 1938. J. A. PAAscHE 2,126,132

cARBuREToR Filed May '7, 1954 k s sheets-sheet s Inverti/'UTP v Jn/5 Pau/57216,

@www CE@ Til Patented Aug. 9, 193s- UNITED sTATEs PATENT OFFICE- v2.12am cannnnn'ron Jens A. Panache, Wilmette, Ill.

Application May 1, 1934, serial No. '124,313

3 claim.A (ci. zel-4s) The present invention relates generally to4 means for vaporizing or carbureting liquid fuel for various purposes as in the production of an explosive mixture for internal combustion engines.

An object of the invention is to provide a novel device of this character which is capable, in operation, of producing a combustible or explosive mixture of fuel andair in an exceedingly iinely divided, dry, smoke-like form.

Another object is to provide an improved fuel carbureting device having means therein for combining a liquid fuel and a `vaporizing gas, usually air, -to reduce the fuel to a thoroughly vaporized condition, and means for subsequently mixing such vaporized fuel intimately with air to pro-v duce an explosive mixture.

Another object is to provide a device of this character having means for varying the volume of the air introduced to vaporize the fuel according to the quantity of fuel, the proportion being suchv as to effect an efficient volatil'ization of the fuel, and which embodies means for variably adjusting the lratio of the quantity oftvolatil.- ized fuel and the volume of the air subsequently added to produce an efliciently explosive mixture. The air which is added in successive steps will hereinafter be termed respectively primary air and secondary air.

Another object is to provide a novel carbureting device wherein the fuel to be carbureted is acted upon by air in separate stages, rst to atomize or volatilize the fuel to effect complete transformation thereof to a gaseous state, and next to introduce air intimately into such gaseous fuel to produce an eiiciently combustible or explosive mixture, said device having fuel and air inlets which are variably controlled to obtain that proportion of air to fuel or fuel mixture which will most efficiently produce the required results.

Another object is to provide, in a device of this character, means for controlling the admission of secondary air which is effective to admit air .practically in measured volume as required by stantly and completely burned or exploded whereby materially to increase the operating eiliciency of the instrumentality to which the fuel is supplied.

Other objects and advantages will become ap- 5 parent in the following description and from the accompanying drawings, in which:

Figure 1 is a substantially axial section through a device embodying the features of the invention, certain associated parts being fragmentary or in 10 elevation.

Fig. 2 is an axial section on an enlarged scale throughthe atomizing or vaporizing section of the device. i

Fig. 3 is a top plan view of a mixing element 1 forming a part of the vaporizing section.

Fig. 4 is a side, elevation of a discharge cap structure for effecting a mixing flow of part of the secondary air stream into the volatilizled fuel.

'Fig. 5 is a transverse section taken as indicated 20 by the line-55 of Fig. 2.

Fig. 6 is an elevational view partially in section looking at the device from the right as shown by Vthe arrows 6-6 in Fig. 1.

' Fig.-7 is a similar viewlooking at the rear side 28 of the device as shown in Fig. 6. i

Fig. 8 is a horizontal section through thevsecondary air valve showing the operating mechanism and parts associated therewith.

Fig. 9 is a detail view of the temperature con- 30 trolled mechanism and the direction in which the view is taken is indicated by the arrows 9--9 in Fig. 6.

Fig. 10 shows the device in elevation as viewed from the left in Fig. 6.

Fig. il is a side face view of the secondary air valve cam assembly.

While the invention is susceptible of various modifications and alternative constructions, I

have shown in the drawings and will herein de- 4o scribe in detail the preferredembodiment, but'it is to be understood that I do not thereby intend to limit the invention to the specific form disclosed, but intend to cover all modifications and alternative constructions falling within the spirit 4i. and scope'oi the invention as expressed in the appended claims.

According to the present invention, the liquid fuel is reduced to an explosive mixture in several stages, the rst of which is the conversion of the liquid fuel into substantially a volatilized condition by the action thereon of a relatively small volume of gas or air which is ample to produce a complete vaporization of the introduced fuel, but is otherwise insumcient to produce an efiiy ciently explosive mixture. The gas and fuel mixture are momentarily confined in a mixing chamber wherein the gas is violently agitated to insure complete volatilization of the fuel. Subsequently, such volatilized ,fuel is thoroughly mixed with air from a secondary air stream, part of the secondary air being drawn into the mixing chamber to produce a thoroughly homogeneous mixture and to further insure that no liquid particle of fuel remains unvaporized. The volume of secondary air admitted is accurately and variably proportioned with respect to the quantity of fuel in the gaseous mixture to produce an eiiicient explosive mixture.

From the following detailed description, a preferred form of device embodying the invention will for illustrative purposes be considered in operative association with an internal combustion engine as an example of a fuel consuming instrumentality. It will be evident, however, that the device may, without substantial modification, be used with instrumentalities other than that shown.

Referring to the drawings, IIJ and II indicate respectively the intake and exhaust manifold of an internal combustion engine. Secured in open communication with the intake manifold is a tubular member I2 which may, if desired, extend through the exhaust manifold but, of course, has no communication therewith. The member I2 constitutes one section of the enclosing member or housing of the fuel vaporizing device, and a continuing housing section I3, suitably secured to the outer free end of the section l2, completes the housing. The section I3 has an angular bend therein to provide a laterally directed tubular end I4 constituting the secondary air intake as will presently be more fully described.

The carburetingdevice embodies mechanism for discharging fuel and a relatively small volume of air into the casing I2 and towardthe intake manifold I0 in a highly volatilized condition. Preferably this mechanism comprises the following arrangement of parts, reference being had particularly to Fig. 1. The outer bend of the section I3,is apertured, as at I5, and about the margin of the aperture is an outstanding flange I6 which is internally screw threaded for engagement by a tubular fitting I1 having an enlarged recess I8 facing inwardly of the housing. Preferably the axes of the fitting and of the recess I8 are located on the axis of the housing. An elongated tube I9 is screw threaded onto the fitting to extend from the base of the recess I8 concentrically through the recess and along the axis of the casing a considerable distance toward the intake manifold. A larger tube has internal screw threaded engagement with the mouth of the recess I8 and extends concentrically along the duct I 9 to provide a passageway 2I therebetween.

The fitting I1 has a laterally extending nipple 22 for connection with the primary air intake controlling means. Internally of the fitting, the passageway 23 through the nipple communicates with the enlarged recess I8 and thence with the passageway 2| which in consequence becomes the primary air conduit. Connected with the nipple 22'is a head 24 (Figs. 1 and 7) having a passageway 25 therein. The passageway is longitudinally angular so that when the parts are assembled the outer end of the passageway opens downwardly into communication with an upright container 28. An induction tube 21 extends from the bottom of the container loosely in'to and a short distance along the passageway 25 (see Fig, 1).A The purpose of the container and tube 21 will hereinafter be described.

Extending horizontally from the head 24 is a boss 28 (Fig. 7) -which is screw threaded externally to receive a valve supporting gland 29. The boss has an axial bore 28a communicating with the passageway 25 preferably at a point below the upper end of the induction tube 21. A rotatable valve 30 in the gland is held in place by cooperating shoulders on the gland and valve and an actuating stem 3I projects through the outer end of the gland for connection with a radial arm 32. The valve has an L-shaped bore 33 therein, one leg of which registers as a continuation of the bore in the boss 28 while the other legis arranged to be moved variably into communication with a primary air inlet port 34 provided in the gland 29.

lThe fitting I1 (Fig. 6) has a second laterally extending nipple 35 thereon which is shown as being located a quarter circumference from the nipple 22. The nipple 35 constitutes the liquid fuel intake and has a bore 36 which communicates with the passage 31 through the tube Iii. The outer or lower end of the tubular fitting I1 has an axial recess 38 (Figs. 1 and 6) therein, the base of which is formed by an annular shoulder 39. A The restricted bore defined by the shoulder forms a sliding bearing for a lower intermediate portion of an elongated valve stem 4U which extends upwardly approximately to the tops of the tubes I9, 20 and downwardly beyond the fitting I1. v

The valve stem controls a fuel inlet valve, to be presently described, and the stem is adapted to be manipulated by means which is supported by an end section 4I provided herein as a detachable continuation of the fitting I1. The abutting ends of the fitting and end section preferably have complementarily formed flared and tapered surfaces 42 for accurately determining the proper relation of one part to the other, and an annular shoulder 43 on the end section is engageable by a gland 44 which is screw threaded over the end of the tting to secure the parts rigidly together. The end section has an axial recess 45 therein which, when the parts are assembled, is a continuation of the recess 38. Together the recesses 38 and 45 receive the spring and packing elements of a conventional compression packing, generally designated at 46, for preventing leakage along the valve stem. The bottom wall 41 of the recess 45 provides a bearing for the valve stem as does a plug 48 in the extreme end wall of the end section.

Between the wall 41 and plug 48, the end section has a generally rectangular transverse opening 49 therethrough for receiving a part of the operating mechanism for the valve stem. vReferring to Figs. 1 and 6, the valve stem, near the bottom wall of the opening 49, has a collar 58 rigidly secured thereto. A lever 5I, which is preferably formed of a metal strip bent transversely into a U-shaped member to straddle the valve stem, is pivoted on the end section, as at 52, and extends laterally and horizontally (as shown) across the collar and beyond the side of the end section. Hence, downward movement of the longer end of the lever moves the valve stem downwardly and the return movement is effected by a spring 53xbearing between the collar 50 and plug 48. Preferably the surfaces of the lever which engage the collar are arcuate, as shown at 54 (Fig. 6), to minimize friction. The lower end of the end section preferably carries such meansas a set screw 55 for adjustable engagement with the short end of the lever and is effective to set the normal or idle position of the valve stem.

'I'he structure of the vaporizing means proper to which the primary air and fuel passageways 2| and 31 respectively lead, may best be seen in Fig. 2. The inner or free end of the tube 28 supports in axial alinement therewith a relatively elongated tubular sleeve 56. Internally the sleeve has enlarged chamber 51 into which the tube I9 extends a short distance beyond the end of the tube 28. 'I'his end of the tube I9 carries an enlargedv head 58 having a tapered external surface 59 for abutment with a complementary surface 60 provided internally of the sleeve 56 at the outer en`d of the. chamber 51. The external surface of the head 58 is mutilated or cut away at a number of equidistantlyv spaced points (see 6I, Fig. to provide clearances 62 between the opposing surfaces of the head and sleeve through which air may flow from the chamber 51. Axially the head has a tapering bore 63 which cooperates with a needle valve 64 of substantial length formed upon the end of a valve stem 40. It is preferred to employ an elongated needle valve in order that the flow of liquid through the bore 63 may be accurately controlled` by minute increments. l

Surrounding the emission mouth of the bore 63 is an annular flange 65 constiutinga tip which internally is fashioned to define an outwardly flaring liquid fuel nozzle 66.' About the flange 65 the sleeve 56 is internally enlarged to provide an air chamber 61 surrounding the flange and communicating with the clearances 62 and the enlargement is terminated rather abruptly by a shoulder 68 located about on the line of the mouth of the nozzley66. The shoulder defines an annular port 69 about the nozzle and from the shoulder the internal wall of the sleeve 56 flares sharply, as indicated at 18, and then terminates in a cylindrical portion 1I. The walls 18 and 1I define a volatilizing chamber 12 in which an exceedingly fine atomization of the fuel stream discharged from the nozzle 66 is attained by the action thereon of the air stream issuing through the port 69.

To produce an intimate mixture of air and fuel particles, aswell as further to insure a complete reduction of fuel particles substantially to a dry, smoke-like gaseous state, means is provided for discharging the vaporized fuel from the chamber 12 in a plurality of relatively small streams and with a whirling action. In this instance, an annular element 13 somewhat in the shape of a hollow cone is fixed in the outer end of the sleeve 56 to traverse the end of the chamber 12 and this element has a circumferentlally spaced series of radially extending slots 14 (Figs. 2 and 3) therein. These slots are quite narrow and are cut through the element in planes which extend transversely of rather than parallel to either the axis or radius of the element. In other words, the stream issues from the slots in a direction which is neither axial nor radial but is generally along a spiral angle so that a circular whirling motion of the stream results. Preferably the central portion of the element is imperforate (see Fig. 3) to eliminate a direct axial flow.

'Ihe secondary air stream is, as Will `become ap. parent, introduced into the housing to flow upwardly about the vaporizing means toward the intake manifold. At least a part of the secondary air is preferably introduced into the circular whirling stream of vaporized fuel whereby to utilize the violent tubulence to effect an intimate of any remaining liquid fuel particles.

mixture of the two streams and final vaporization Thus, the upper end of the sleeve 56 has screw threaded thereonto an elongated discharge cap 15 which may be held in any position of axial adjustment by such means as a lock nut 16. The cap has a cylindrical side wall 82 in which an annular series of spaced slots 11 (Figs. 2 and 4) is formed, which slots in assembly are located immediately above the upper surface of the element 13. The slots are also formed generally on a spiral angle as l in the case of the element slots 14 and the whirling action of the volatilized fuel mixture causes an inward flow of secondary air through the slots 11 and into the fuel mixture.

At its upper end the cap is closed by a conically shaped head 18v which extends annularly beyond the cylindrical side wall to form a flange ,19. 'Ihe head also has a series of slots 88 therein formed to discharge the fuel mixture into the interior of casing section l2 and toward the lintake manifold on a spiral angle. The annular flange 19 faces away from the intake manifold I0, and is dimensioned to form with the surrounding Wall of the tubular casing a passageway 8| for `the remaining part of the secondary air stream.

It is preferred, in order to prevent condensation ofthe vaporized fuel, to provide sharp edges at the discharge ends of all of the passageways through whichrthe vaporized material flows. Air expanding through an opening or port having blunt edges creates turbulence or eddy currents around the port which do not prevent' the condensation of vaporized fuel due to the cooling action of the expanding fuel stream as it issues through the port. By providing a substantially knife edge around the port, the expanding uid discharged therefrom induces a flow of air along the knife surface outside of the stream and into the stream to draw into the stream any particles tending to condense. Thus, the annular flange 65 and the slots 14 and 80 are fashioned to present substantially knife edges at the discharge sides thereof thereby minimizing condensation.

Referring to Figs. 1, 6 and 7, liquid fuel is delivered to the fuel nipple 35 through a conduit 84 which is connected with a conventional type of fuel pump 85 and lter 86. It may be desirable to preheat the fuel before delivery to the carburetor, and in this embodiment this end is attained by forming an intermediate coil 81 in the conduit, enclosing said coil in a leak proof casing 88 secured to the exhaust manifold ll, and diverting a portion of the hot exhaust gases through the casing 4by such means as a cap 89 in the exhaust manifold communicating with the casing through an intake slot 98 and a similar cap 9| having a discharge slot 92 therein for returning the gases to the manifold. To produce circulation through the casing 88, the intake slot which herein is the slot 9i) faces toward the gas flow through the exhaust manifold while the `other slot 92 is oppositely faced.

The construction and arrangement of parts by which the admission f secondary air is effected and controlled will now be described. 'I'he face of the tubular end I4 of casing section I3 is beveled, as at 93 (Figs. l and 8), to form a valve seat for a circular secondary air valve 94. The valve is supported for axial reciprocatory movement in any suitable manner, as by a curved arm 95 projecting endwise from the casing and having an axially alined bearing 96 for a stem `91 on the valve. A nut 98 onv the stem adjustably limits the closed position ofthe valve while a spring 90, about the stem and exerting its force between the valve and the bearing, normally urges the valve toward its seat.

The type of valve herein shown is capable oi' joumaled in the associated wall. The shaft carries an elongated sleeve |0| which is loose on the shaft and is journaled in the other casing wall. The sleeve extends inwardly approximately to a point opposite the center of the valve 94 and on its inner end has a cam |02 fixed rigidly thereto for engagement with the adjacent face yof the valve. The shape of the cam is accurately predetermined to produce an accurately graduated opening and closing of the valve upon rotation of the sleeve.

The present invention embodies a temperature control means for automatically varying the admitted volume of secondary air as such adjustment becomes necessary during operation of the device whereby to maintain the explosive mixture at its maximum eiiiciency. For example, in internal combustion engines tlie carbureting mechanism is usually set for operation at an average or mean temperature. An eilciently combustible mixture at this temperature will not, however, be eillcient at a different temperature. Hence, while the engine is heating it is operating inefliciently, and atmospheric temperature changes have the same effect.

The present temperature control. means embodies a lost motion connection between the shaft |00 and sleeve 0| which, while it allows the sleeve to be moved by the shaft, also permits of independent movement of the sleeve according to the action of a thermally responsive device. Referring to Fig. 11, the side face of the cam |02 at the end of sleeve |0| has a sector shaped recess |03 therein. The sleeve |0| is circumferentially cut away through that part which opposes the recess to allow a pin |05, rigid with the shaft |00, to extend into the recess, A spacing sleeve or collar interposed between the end of the sleeve |0| and the casing wall maintains the centered relationship of the valve and cam and also substantially closes the open face of the recess |03. As shown in Figs. 8 and 9, the shaft beyond the outer end of the sleeve has one end of a spirally wound bimetallic thermally responsive strip |06 secured thereto, as at |01. The other end of the strip is fastened rigidly to the sleeve, as by the adjustable clamping device |00.

'I'he operation of this particular part of the mechanism maybe best understood byconsidering that the cam |02 will normally be rotated in a counterclockwise direction to open the valve. The mechanism being properly adjusted for eilicient operation, the pin |05 at'minimum temperature engages one end of recess |03 (the lower end as the parts are shown in Fig. 11). Counterclockwise movement of the shaft to open the valve will accordingly be transmitted to the cam through the pin |05. As the temperature increases, the bimetallic strip is arranged to exert a force on the sleeve |0| which rotates the -with the associated parts.

cam counterclockwise or advances the cam to open the valve, thus admitting additional secondary air in proportion to temperature increase. Experimentation will determine the proper relationship between the several forces involved, as well as the speed of the cam and the shape of its surface so that the increased volume of secondary air admitted as temperature increases will be in proper proportion to the fuel to produce an efficiently explosive mixture at any temperature. If the temperature decreases, the therfrom the shaft. If desired, an air filter of con-' ventional form may be connected with the secondary air inlet, as illustrated in dotted outline in Fig. 1.

Herein the manipulable means by which the operator conventionally controls engine operation is represented generally by the end of a power transmitting connecting rod H0 (Fig. 1) a thrust being theA valve opening movement. This rod is suitably connected through a link with the shaft |00 inlsuch manner that a push or pull on the rod ||0 rotates the shaft correspondingly to open or close the secondary air inlet valve. Such operator controlled movements are also utilized to actuate the fuel inlet valve 64 and the primary air inlet valve 30.

Referring to Figs. 6, 7 and 10, the end of shaft |00, opposite that to which link is connected, is engaged by a split clamping member ||2 which has a longitudinal screw threaded extension ||3 thereon. Preferably, both ends of shaft |00 are serrated to provide a non-slipping connection The extension 3 engages a nut ||4 which is pivotally supported between the arms l5 of a yoke 6 forming the upper end of an actuating link assembly, generally designated The link assembly depends from the nut ||4 and at its lower end terminates in a head H08 which is receivable between the arms of the needle valve actuating lever 5| and is plvotally secured thereto, as shown at H9, at one of several positions provided along the length of the lever. This adjustment, together with that provided by the nut ||4 and extension H3, serve generally to establish the desired operating relationship between the shaft |00 and lever 5|. However, a finer and more accurate adjustment is usually necessary and means has been provided for attaining this end with micrometer-like accuracy.

To this end, the link assembly is formed in sections. The lower section |20 which carries the head ||8 and is connected with the lever 5| has 4 an externally screw threaded upper end as shown in Fig. 6. An intermediate section |22 is tubular and one end thereof has a swivel connection with a stem |23 on yoke 6, said yoke being the third section of the link assembly 'I'he opposite end of the tubular section |22 is internally screw threaded for ermagement with the screw threads of the lower section |20. This end of section |22 is slotted as shown at |24 (Fig. 10), is externally tapered, andy is 'screw threaded for engagement by a complementary nut |2| carried by section the effective length of the link assembly II1,

after which the adjustment may be definitely and rmly maintained by engagement between section |22 and nut I2 I. Thus, the overall length of` the link assembly H1. may be `readily increased or decreased and such adjustment may be made vwith exceeding accuracy.

Actuation of the shaft |00 by the operator will, therefore, be effective through the above described connections to open and close the needle yvalve 64 as the secondary air valve 94Jis correspondingly actuated and the intermediate connections are so accurately adjustable that the most efficient proportion of secondary air to fuel may be obtained. i

The primary air valve 30 is controlledv by the movements of the lever 5I by such means as a` only suilicient to produce an efficient vaporization' of the fuel.

In adjusting the device for operation, the fuel valve 64 and the primary air valve 30 are setto a normal, slightly open position which determines the idling or minimum' speed of operation of the engine; The adjustments are correlated in such manner that at the idling speedthe fuel which.

is introduced will be acted on by just that volume of primary air necessary to produce a complete atomization of the fuel. The secondary air valve 94 is valso adjusted to aninitial slightly open position, such as will produce an efciently combustible mixture of fuel and air at a predeterf minedaverage temperature, which may be approximately the minimum ytemperature at which the engine will be operated.

These adjustments having been made, fuel is Adelivered from the pump 65 by conduit 84, duct 36,

and passageway 31 to discharge through the tapering bore 63 and nozzle 66. Primary air is drawn into the device throughport 34, bore 33 in air valve 30, bore 28, passages 23- and 21,*

fuel discharge nozzle 66. The force which causes such primary' air flow is the diminished pressure in the intake manifold and in some measure the inductive action of the discharging fuel stream. The wall which defines the fuel discharge nozzle flares outwardly (see Fig. 2) to produce a divergent discharge of fuel into-the encircling air stream whereby to produce a violent turbulence in the volatilizing chamber with the result that the fuel stream is broken up into exceedingly finely divided particles. This volatilized fuel then passesfthrough the slots 'i4 in the element 13 and the several streams issuing from the slots encounter the internal wall of the cap l5 and a whirling action within said chamber results. This motion serves to draw secondary air through the slots 'l1 and an intimate mixture of the streams is produced. The passage of the fuel and air mixture through the slots, together withnthe subsequent mixing of the vaporized fuel with a part of the secondary air, completes the atomization of the fuel into its finest possible state and pro- 2 duc-es a completely homogeneous mixture of fuel flange 19 to meet the diverging fuel mixture stream. Consequently a final thorough mixing of the fuel and air streamsoccurs as the fuel mixture travels to they intake manifold to produce a mixture which is in its most eiciently. combustible state.

Variations in secondary air requirements, caused by increasing or decreasing temperature, are met by the action of the thermally responsive means associated with the secondary air valve. Consequently, the proper volume of air is mixed with the fuel and the fuel cannot vary from a too lean to a too rich mixture because of temperature changes.

The cam actuator for the secondary air valve and the elongated needle valve permit the actions of these two Valves to be accurately correlated and the proportion of the substances admitted can be denitely adjusted and maintained.

The purpose of the container 26 is to receive excess and unused fuel which might occasionally pass from the fuel duct, as would possibly occur when the engine is stopped. Such fuel drains downwardly through the primary air passageways 2l and 23 and into the container where it is retained until the engine is started. Thereupon the initial lloW of primary air will, as it :sov

passes the mouth of induction tube 21, draw the fuel from the container and discharge it from the vaporizing device to produce a rich fuel mixture. Consequently the action is similar to the Operation of choking an engine in starting.

The present device has been illustrated as being of the type known commercially as an updraft carburetor. However, without substantial modiiication it will also serve effectively as a down-draft carburetor, it being necessary merely to turn the device upside down through Of course, in the last mentioned position the container 26 and its associated induction tube are not required since any unused fuel will iow to the intake manifold and be available there in starting.

yIt will be seen moreover that the present device is capable of operation in positions other 1. In a device of the character described, the

combination of a chamber having an outlet, means for delivering an atomized mixture of fuel and air to said chamber for discharge from said outlet, a member in said chamber having slots extending generally radially and formed on an angle. more nearly transverse of the axis of the chamber than parallel for imparting a whirling action to the mixture, means for imparting a whirling movement to the streamflowing from said outlet, a casing in which said chamber is located and into which said stream is discharged, and means for delivering air to said casing for discharge into the whirling fuel stream.

2. In a carbureting device of the character described, the combination of an air intake, a valve for controlling the volume of air entering through said intake, means mounted adjacent the valve for controlling said valve and including a coaxial shaft and sleeve, a cam mounted on said sleeve and arranged to move said valve to open position, actuating means for rotating said shaft, and thermally responsive means connecting said shaft and sleeve for joint rotation to move said cam and thereby adjust the position of said valve for various operative conditions, said thermally responsive means being movable due to variations in temperature for effecting relative rotation between said shaft and sleeve to shift the circumferential position of said sleeve and cam on the shaft to move said valve for variabiy governing the volume of air admitted into said intake in any adjusted position established by said actuating means.

3. In comblnationin a carburetor construction of the character described, an elongated fuel delivery passage having a restricted discharge port, a needle valve for accurately controlling the discharge of liquid fuel from said port and having a valve stem extending therefrom to the opposite end of said passage, a primary air passage having its discharge end coactive with said fuel discharge port to produce an atomized fuel-air stream, 'a valve for controlling the ow of primary air through said air passage, a secondary air passageway arranged for supplying a, large volume stream of air to combine with said fuel air stream to produce an efficient combustible mixture, a valve for controlling the volume of air ilow in said secondary passageway', means for adjusting the secondary air valve including an operating shaft and means for actuating the saine, a lever operatively associated with the end of said needle valve stem for adjusting the same longitudinally and having an adjustable con-- nection with said shaft for operation thereby, and means connecting said lever with said primary air valve for effecting adjustment of the latter simultaneously with said needle valve.

' JENS A. PAASCHE. 

